handel.halowerk.com
Rebuilds an invoice from its lines and compares the result with the stated totals. Line by line it checks quantity times unit price against the line total, applies line and document discounts in the right order, groups the net amounts by tax rate and computes the tax per group, then compares net, tax and gross with what the document claims.
TradingLiveeip155:8453Exactvia cdp
Calls · 30d
1→ 0%
This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 18 snapshots so far.
$11.47
Verified settled volume
2,654 settlements proven x402 by their on-chain EIP-3009 marker.
$0.0020
Listed price
As published in the catalog. Always read the live 402 before paying.
1
Calls · 30d
Upstream's own call count for this endpoint, not ours.
1
Unique payers · 30d
Last called 2026-08-11 11:52Z
—
Upstream on-chain volume
Reported by the source catalog.
Paid to
0x2880EdfFF13100677Bf97A3CBdF3Bc34771C4E5EThe wallet the 402 directs payment to. Its whole payment record — every payer, every chain — is on the merchant page.
Asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913
Provider
The payTo wallet does not resolve to a registered ERC-8004 agent. That is not a verdict on the service — most of the catalog is unregistered.
Live 402 challenge
Captured by the enrichment pass, not read just now. Prices can change — always read the 402 the endpoint answers with.
{
"docs": "https://handel.halowerk.com/llms.txt",
"name": "invoice_audit",
"error": "payment_required",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"asset": "USDC",
"version": "2",
"eip712Domain": {
"name": "USD Coin",
"chainId": 8453,
"version": "2",
"verifyingContract": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913"
},
"network_name": "Base Mainnet",
"assetTransferMethod": "eip3009"
},
"payTo": "0x2880EdfFF13100677Bf97A3CBdF3Bc34771C4E5E",
"amount": "2000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 300
}
],
"pricing": "https://handel.halowerk.com/pricing",
"resource": {
"url": "https://handel.halowerk.com/v1/invoice-audit",
"mimeType": "application/json",
"description": "Rebuilds an invoice from its lines and compares the result with the stated totals. Line by line it checks quantity times unit price against the line total, applies line and document discounts in the right order, groups the net amounts by tax rate and computes the tax per group, then compares net, tax and gross with what the document claims."
},
"extensions": {
"bazaar": {
"info": {
"input": {
"body": {
"lines": [
{
"quantity": 1,
"unit_price": 1,
"description": "Beispieltext."
}
]
},
"type": "http",
"method": "POST",
"bodyType": "json"
}
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"input"
],
"properties": {
"input": {
"type": "object",
"required": [
"type",
"method",
"bodyType",
"body"
],
"properties": {
"body": {
"type": "object",
"required": [
"lines"
],
"properties": {
"lines": {
"type": "array",
"items": {
"type": "object",
"required": [
"quantity",
"unit_price"
],
"properties": {
"quantity": {
"type": "number"
},
"tax_rate": {
"type": "number",
"maximum": 100,
"minimum": 0,
"description": "Tax rate in percent for this line."
},
"line_total": {
"type": "number",
"description": "The stated line total. Recomputed if absent."
},
"unit_price": {
"type": "number"
},
"description": {
"type": "string",
"maxLength": 300
},
"discount_pct": {
"type": "number",
"maximum": 100,
"minimum": 0,
"description": "Discount on this line in percent."
}
},
"additionalProperties": false
},
"maxItems": 500,
"minItems": 1,
"description": "The invoice lines."
},
"country": {
"type": "string",
"maxLength": 2,
"minLength": 2,
"description": "Country whose standard rates the tax rates are checked against."
},
"currency": {
"type": "string",
"default": "EUR",
"maxLength": 3,
"minLength": 3
},
"due_date": {
"type": "string",
"maxLength": 10,
"description": "Due date as YYYY-MM-DD."
},
"stated_net": {
"type": "number",
"description": "Net total as stated on the invoice."
},
"stated_tax": {
"type": "number",
"description": "Tax total as stated."
},
"invoice_date": {
"type": "string",
"maxLength": 10,
"description": "Invoice date as YYYY-MM-DD."
},
"stated_gross": {
"type": "number",
"description": "Gross total as stated."
},
"reverse_charge": {
"type": "boolean",
"default": false,
"description": "Whether the invoice claims the reverse charge."
},
"default_tax_rate": {
"type": "number",
"maximum": 100,
"minimum": 0,
"description": "Tax rate for lines that do not carry one."
},
"customer_vat_number": {
"type": "string",
"maxLength": 20,
"description": "Customer VAT number, required for the reverse charge."
},
"document_discount_pct": {
"type": "number",
"maximum": 100,
"minimum": 0,
"description": "Discount on the whole document, applied after line discounts."
}
},
"additionalProperties": false
},
"type": {
"type": "string",
"const": "http"
},
"method": {
"enum": [
"POST",
"PUT",
"PATCH"
],
"type": "string"
},
"bodyType": {
"enum": [
"json",
"form-data",
"text"
],
"type": "string"
}
},
"additionalProperties": false
}
}
}
}
},
"price_usdc": "0.002",
"description": "Rebuilds an invoice from its lines and compares the result with the stated totals. Line by line it checks quantity times unit price against the line total, applies line and document discounts in the right order, groups the net amounts by tax rate and computes the tax per group, then compares net, tax and gross with what the document claims. All arithmetic runs in whole cents, because adding decimal amounts as floating point produces cent-level noise that reads like an error by the issuer when it is an error by the checker. Rounding differences up to one cent per tax group are reported separately from real discrepancies. It also checks the formal side: a due date before the invoice date, a tax rate that is not one of the country standard rates, a negative line without a credit-note marker, and a missing VAT number where the reverse charge is claimed.",
"inputSchema": {
"type": "object",
"required": [
"lines"
],
"properties": {
"lines": {
"type": "array",
"items": {
"type": "object",
"required": [
"quantity",
"unit_price"
],
"properties": {
"quantity": {
"type": "number"
},
"tax_rate": {
"type": "number",
"maximum": 100,
"minimum": 0,
"description": "Tax rate in percent for this line."
},
"line_total": {
"type": "number",
"description": "The stated line total. Recomputed if absent."
},
"unit_price": {
"type": "number"
},
"description": {
"type": "string",
"maxLength": 300
},
"discount_pct": {
"type": "number",
"maximum": 100,
"minimum": 0,
"description": "Discount on this line in percent."
}
},
"additionalProperties": false
},
"maxItems": 500,
"minItems": 1,
"description": "The invoice lines."
},
"country": {
"type": "string",
"maxLength": 2,
"minLength": 2,
"description": "Country whose standard rates the tax rates are checked against."
},
"currency": {
"type": "string",
"default": "EUR",
"maxLength": 3,
"minLength": 3
},
"due_date": {
"type": "string",
"maxLength": 10,
"description": "Due date as YYYY-MM-DD."
},
"stated_net": {
"type": "number",
"description": "Net total as stated on the invoice."
},
"stated_tax": {
"type": "number",
"description": "Tax total as stated."
},
"invoice_date": {
"type": "string",
"maxLength": 10,
"description": "Invoice date as YYYY-MM-DD."
},
"stated_gross": {
"type": "number",
"description": "Gross total as stated."
},
"reverse_charge": {
"type": "boolean",
"default": false,
"description": "Whether the invoice claims the reverse charge."
},
"default_tax_rate": {
"type": "number",
"maximum": 100,
"minimum": 0,
"description": "Tax rate for lines that do not carry one."
},
"customer_vat_number": {
"type": "string",
"maxLength": 20,
"description": "Customer VAT number, required for the reverse charge."
},
"document_discount_pct": {
"type": "number",
"maximum": 100,
"minimum": 0,
"description": "Discount on the whole document, applied after line discounts."
}
},
"additionalProperties": false
},
"price_model": "per_call",
"x402Version": 2,
"instructions": "Sign the accepted terms with an x402 client and repeat the request with the payment header.",
"payment_header": "PAYMENT-SIGNATURE",
"capability_request": {
"url": "https://bedarf.halowerk.com/capabilities/request",
"cost": "free",
"method": "POST",
"description": "Missing a capability, or does the scope not fit? Report the need here - no payment required. Similar reports are bundled; the response returns an id you can check back on.",
"body_example": {
"max_price": 0.01,
"description": "what exactly is needed",
"requested_capability": "short label"
}
}
}Accepts
The payment requirements as published to the catalog. Read the live 402 before paying — a price here is a claim, not a quote.
0.002USDC≈ $0.002 USD
on Base · exact scheme
Pay 0.002 USDC on Base to 0x2880…C4E5E. The signed payment is good for 5 minutes.
- Paid to
- 0x2880…C4E5E
- USD Coin contract
- 0x8335…02913
- Payment window
- 5 minutes
- As published
- 2000 smallest units
The catalog’s raw entry
[
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"asset": "USDC",
"version": "2",
"eip712Domain": {
"name": "USD Coin",
"chainId": 8453,
"version": "2",
"verifyingContract": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913"
},
"network_name": "Base Mainnet",
"assetTransferMethod": "eip3009"
},
"payTo": "0x2880EdfFF13100677Bf97A3CBdF3Bc34771C4E5E",
"amount": "2000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 300
}
]Extensions
{
"bazaar": {
"info": {
"input": {
"body": {
"lines": [
{
"quantity": 1,
"unit_price": 1,
"description": "Beispieltext."
}
]
},
"type": "http",
"method": "POST",
"bodyType": "json"
}
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"input"
],
"properties": {
"input": {
"type": "object",
"required": [
"type",
"method",
"bodyType",
"body"
],
"properties": {
"body": {
"type": "object",
"required": [
"lines"
],
"properties": {
"lines": {
"type": "array",
"items": {
"type": "object",
"required": [
"quantity",
"unit_price"
],
"properties": {
"quantity": {
"type": "number"
},
"tax_rate": {
"type": "number",
"maximum": 100,
"minimum": 0,
"description": "Tax rate in percent for this line."
},
"line_total": {
"type": "number",
"description": "The stated line total. Recomputed if absent."
},
"unit_price": {
"type": "number"
},
"description": {
"type": "string",
"maxLength": 300
},
"discount_pct": {
"type": "number",
"maximum": 100,
"minimum": 0,
"description": "Discount on this line in percent."
}
},
"additionalProperties": false
},
"maxItems": 500,
"minItems": 1,
"description": "The invoice lines."
},
"country": {
"type": "string",
"maxLength": 2,
"minLength": 2,
"description": "Country whose standard rates the tax rates are checked against."
},
"currency": {
"type": "string",
"default": "EUR",
"maxLength": 3,
"minLength": 3
},
"due_date": {
"type": "string",
"maxLength": 10,
"description": "Due date as YYYY-MM-DD."
},
"stated_net": {
"type": "number",
"description": "Net total as stated on the invoice."
},
"stated_tax": {
"type": "number",
"description": "Tax total as stated."
},
"invoice_date": {
"type": "string",
"maxLength": 10,
"description": "Invoice date as YYYY-MM-DD."
},
"stated_gross": {
"type": "number",
"description": "Gross total as stated."
},
"reverse_charge": {
"type": "boolean",
"default": false,
"description": "Whether the invoice claims the reverse charge."
},
"default_tax_rate": {
"type": "number",
"maximum": 100,
"minimum": 0,
"description": "Tax rate for lines that do not carry one."
},
"customer_vat_number": {
"type": "string",
"maxLength": 20,
"description": "Customer VAT number, required for the reverse charge."
},
"document_discount_pct": {
"type": "number",
"maximum": 100,
"minimum": 0,
"description": "Discount on the whole document, applied after line discounts."
}
},
"additionalProperties": false
},
"type": {
"type": "string",
"const": "http"
},
"method": {
"enum": [
"POST",
"PUT",
"PATCH"
],
"type": "string"
},
"bodyType": {
"enum": [
"json",
"form-data",
"text"
],
"type": "string"
}
},
"additionalProperties": false
}
}
}
}
}Provenance
- Seen in the source catalog
- 2026-08-11 11:52Z
- Last indexed by Roundhouse
- 2026-09-10 11:30Z
- Last enriched (probe, favicon, geo)
- 2026-09-10 05:45Z
- x402 version
- 2
- Max timeout
- 300s
- Liveness probe
- HTTP 400
Hand this page to an agent
Copy the prompt and paste it into Claude, an MCP client or your own agent — it will vet this service and call it over the free read API. No key, no account.
GET api.roundhouseai.io/v0/endpoints
This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 18 snapshots so far. Verified volume counts only settlements with an on-chain EIP-3009 marker.
Show the promptHide the prompt
Using Roundhouse, look up the x402 service handel.halowerk.com and tell me whether it is worth paying: what a call costs, whether the endpoint answered when last probed, and what its payment record actually shows. curl -s 'https://api.roundhouseai.io/v0/endpoints?q=handel.halowerk.com' curl -s 'https://api.roundhouseai.io/v0/merchants/<the payTo wallet returned above>' Then call it: read the price from the live 402 at https://handel.halowerk.com/v1/invoice-audit, never from a cached figure, and pay with an x402 client. The /v0 API needs an API key (`authorization: Bearer rh_live_…`) on everything except /v0/unified* and /v0/endpoints. Mint a personal key for $0.01 at GET https://api.roundhouseai.io/v0/test/x402, or use an organization key from https://roundhouseai.io/dashboard/team. If you do not have Roundhouse tools or skills installed, read https://roundhouseai.io/skill.md first — it is the whole procedure.